TY - JOUR T1 - Lesion Area Detection Using Source Image Correlation Coefficient for CT Perfusion Imaging JF - IEEE Journal of Biomedical and Health Informatics Y1 - 2013 A1 - Fan Zhu A1 - Rodríguez, David A1 - Carpenter, Trevor K. A1 - Atkinson, Malcolm P. A1 - Wardlaw, Joanna M. KW - CT , Pattern Recognition , Perfusion Source Images , Segmentation AB - Computer tomography (CT) perfusion imaging is widely used to calculate brain hemodynamic quantities such as Cerebral Blood Flow (CBF), Cerebral Blood Volume (CBV) and Mean Transit Time (MTT) that aid the diagnosis of acute stroke. Since perfusion source images contain more information than hemodynamic maps, good utilisation of the source images can lead to better understanding than the hemodynamic maps alone. Correlation-coefficient tests are used in our approach to measure the similarity between healthy tissue time-concentration curves and unknown curves. This information is then used to differentiate penumbra and dead tissues from healthy tissues. The goal of the segmentation is to fully utilize information in the perfusion source images. Our method directly identifies suspected abnormal areas from perfusion source images and then delivers a suggested segmentation of healthy, penumbra and dead tissue. This approach is designed to handle CT perfusion images, but it can also be used to detect lesion areas in MR perfusion images. VL - 17 IS - 5 ER - TY - JOUR T1 - An open source toolkit for medical imaging de-identification JF - European Radiology Y1 - 2010 A1 - Rodríguez, David A1 - Carpenter, Trevor K. A1 - van Hemert, Jano I. A1 - Wardlaw, Joanna M. KW - Anonymisation KW - Data Protection Act (DPA) KW - De-identification KW - Digital Imaging and Communications in Medicine (DICOM) KW - Privacy policies KW - Pseudonymisation KW - Toolkit AB - Objective Medical imaging acquired for clinical purposes can have several legitimate secondary uses in research projects and teaching libraries. No commonly accepted solution for anonymising these images exists because the amount of personal data that should be preserved varies case by case. Our objective is to provide a flexible mechanism for anonymising Digital Imaging and Communications in Medicine (DICOM) data that meets the requirements for deployment in multicentre trials. Methods We reviewed our current de-identification practices and defined the relevant use cases to extract the requirements for the de-identification process. We then used these requirements in the design and implementation of the toolkit. Finally, we tested the toolkit taking as a reference those requirements, including a multicentre deployment. Results The toolkit successfully anonymised DICOM data from various sources. Furthermore, it was shown that it could forward anonymous data to remote destinations, remove burned-in annotations, and add tracking information to the header. The toolkit also implements the DICOM standard confidentiality mechanism. Conclusion A DICOM de-identification toolkit that facilitates the enforcement of privacy policies was developed. It is highly extensible, provides the necessary flexibility to account for different de-identification requirements and has a low adoption barrier for new users. VL - 20 UR - http://www.springerlink.com/content/j20844338623m167/ IS - 8 ER -